
Mega Doctor News
Following the severe thunderstorms and record-breaking rainfall in Deep South Texas last week, Rio Grande Valley residents have been left dealing with the aftermath of flash flooding across the four-county region.
Aside from cleaning up the damage and debris associated with last week’s torrential downpours, people from Brownsville to Roma are dealing with an increased risk of dengue fever and other mosquito-borne illnesses.
Common in tropical and subtropical climates, dengue fever is a viral infection that spreads from mosquitoes to people. In the United States, there were nearly 3,000 cases of dengue fever reported in 2024, per the Centers for Disease Control and Prevention. In the Valley, nine cases were reported at South Texas Health System facilities alone last year. This year, one case of dengue fever has been reported at an STHS facility to date.
But health experts warn that the flooding caused by last week’s heavy rainfall may lead to dengue fever outbreaks because standing water is the ideal breeding ground for mosquitoes.
“The rapid increase in mosquito populations after a flood event like the one we experienced last week can lead to a higher risk of dengue transmission, as more mosquitoes are available to bite and spread the virus,” says Eduardo Candanosa, MD, a family and emergency medicine physician affiliated with South Texas Health System’s freestanding emergency departments. “Moreover, floods often displace people from their homes, leading to crowded conditions in shelters or temporary housing, which can further facilitate the spread of dengue as people are more exposed to mosquitoes.”
“It’s important for the community to understand the symptoms and take precautions against dengue fever, especially in those hardest-hit areas,” says Dr. Candanosa. “While dengue fever can cause symptoms like high fever, headache and body aches, many people infected with the dengue virus experience only mild ones, making a diagnosis difficult.”
When symptoms do occur, they can be mild and like the flu, including high fever, headache, body aches, nausea and vomiting. In some cases, dengue can progress to a more severe form, dengue hemorrhagic fever (DHF), which can be life-threatening. DHF can cause severe abdominal pain, persistent vomiting, bleeding (gums, nose, etc.), and in severe cases, shock. It can also lead to a sudden drop in blood pressure and even death.
“Severe dengue fever can develop quickly and is considered a life-threatening medical emergency,” says Dr. Candanosa. “So, it’s important to seek immediate medical attention if you or a loved one experiences a high fever that’s difficult to control along with generalized weakness, headaches, severe stomach aches, bleeding and persistent vomiting. Call 911 or go to your nearest emergency room.”
To help avoid dengue outbreaks following the region’s recent flooding, South Texas Health System offers the following prevention tips to protect you and your loved ones:
• Remove standing water: After a flood, stagnant water pools can become breeding grounds for mosquitoes, so it’s important to eliminate them. That includes discarded tires, clogged gutters and air conditioner drip trays.
• Empty and scrub containers: Regularly drain and clean containers that hold water like tarps, buckets, toys, pools, birdbaths, flowerpot saucers or trash containers.
• Tidy up your yard: Keep your yard and surrounding areas tidy to prevent the accumulation of water-holding items.
• Keep mosquitoes out of your home: Repair holes in screens and keep windows and doors closed to ensure mosquitos don’t have a way in.
• Stay indoors during peak mosquito activity: Avoid being outdoors during peak mosquito biting hours, which are typically dawn and dusk.
• Use insect repellent: When spending time outside, apply insect repellent to exposed skin. Use an EPA-registered repellant that contains 20-30% DEET or other ingredients known to keep mosquitos away.
• Wear protective clothing: Wear loose-fitting, long-sleeved shirts and pants to cover your skin.
“The best way to prevent dengue fever is to avoid getting bit by mosquitoes,” says Dr. Candanosa. “By adhering to these tips, you can reduce your risk for dengue fever, as well as other mosquito-borne illnesses.”
If you suspect you or a loved one has dengue fever, seek immediate medical attention.